DIP Section SMT Supervision Focus and Exception Handling

1.Solder Paste Printing Quality.

It directly impacts the quality of component welds.

Symptoms of poor solder paste quality include:

Solder Paste Voids: solder paste does not completely fill the circuit board and forms
voids.

Overflow of solder paste: When solder paste is overflowing on the PCB it affects
component soldering.

Uneven Distribution of Solder Paste: On the PCB there is an uneven distribution of
solder. This affects component soldering.

The following are the main causes of abnormal solder paste print quality:

• The solder paste printer’s parameters are incorrectly set.

• The solder paste printing is not cleaned enough

• Poor solder paste quality.

How to handle abnormal solder paste print quality

• Set the parameters for the solder paste printing device.

• The solder paste is a printer that needs to be cleaned.

• Replace solder paste.

2.Component Mounting Position

The component placement position is a vital quality indicator of SMT assembly. It directly impacts
product performance and reliability.

The most common manifestations of component placement abnormalities are:

Offset: The component is offset from its specified position.

Misalignment: Position of the component does not match that specified.

Missing Placement: This component is not mounted.

The most common reasons for abnormal component positioning are:

• Setting improper placement machine parameters.

• The SMT Pick and Place machine is not cleaned enough

• Poor component quality.

How to handle abnormal component mounting positions:

• Adjust the parameters of the placement machine.

• Clean the placing machine.

• Replace components.

3. Component Welding Quality

Component welding is a significant indicator of quality in SMT. It directly impacts product performance
and reliability.

The most common signs of poor component welding quality include:

Cold-solder joint: Insufficient solder at the soldering points and insufficient welding
strength.

Open Solder joint: The solder falls out.

The following are the main causes of abnormal component welding:

• The parameters of the welding furnace are not correctly set.

• The welding machine is not sufficiently clean.

• Poor component quality.

How to deal abnormal component welding quality

• Adjust the welding parameters.

• Clean the welding machine.

• Replace components.

4. Prevention First

Prevention is the key principle in SMT IPQC surveillance focus and abnormal handling.

We can only detect problems early and correct them if we strengthen the monitoring of component
placement and solder paste printing. It prevents quality issues from occurring.

5. Quick Response

We should act quickly to prevent the problem from getting worse.

It can lead to product recalls and quality issues if not addressed immediately.

6. Record Tracking

To prevent similar situations from occurring again, all abnormal events should be tracked, analysed, and
summarized.

We can improve the quality of our products by analyzing abnormalities and identifying their causes.

We can reduce production costs and improve the quality of products by strengthening the supervision and
controls over DIP segment SMT.